Fuse 8 on LB but not radio

[TheStinkyHippy]

I have fuse 8 on my leisure battery, so blinds, 12v sockets and radio are all powered when key is out.

However, I think the radio drains the battery as it is on all the time.
I would like to put the radio back onto ACC, but leave blinds and sockets on LB.
Has anyone done this?

Any idea where the wire out of original fuse 8 goes so I can find the wire that goes off to radio.

Thanks

[Simon Jones]

You can do it if you dont mind chopping around with the wiring. I wanted the option to use it on either battery so fitted a switch in one of the blanks to the left of the steering wheel which feeds a relay powered by the LB. When switched on, the relay is energised and radio is powered by the LB and when switched off, it reverts to ignition switched.

[g8dhe]

This can be a problem, easiest place to intercept the radio connections is at the connector behind the radio itself (you really don't want to open the loom itself up!) , you can disconnect and transfer either or both the main power connection (A7) or standby connection (A4) back to the original circuit using an additional wire back to the original fuse or add an extra switch to really isolate the radio. Worth measuring the currents drawn in both circuits with a meter to see which is the culprit if possible

[TheStinkyHippy]

Got round to working on this at the weekend, thanks for the very useful diagrams.
I have wired a switch so the radio 12v switched connection is either from SB Acc, or from LB..

While working on this I found that whoever fitted the BMW clock had wired the clock light into the 12v switched connection, so the light was on all the time.. which would explain why battery was draining!
Correctly moved that to the 'lights' circuit and today the LB is holding charge lovely..

wish the rust was as easy to solve.